BeneFIT PT’s Anatomy Series Vol.2: the Shoulder

Last month we kicked off BeneFIT  Physical Therapy’s Anatomy  Blog Series. Each month we will feature a different part of the body. BeneFIT PT staff is highly trained in knowing all about human anatomy so that we can effectively help our patients with their specific areas of concern, rehabilitation and strenghthening.


The exercises you get in Physical Therapy are specifically targeted to the part, or parts, of the body that need strenthening, rehabilitation or treatment. No two patients will have the same treatment plan, but in general we all have the same basic bone structure.

Remember the Children’s Song “Head, Shoulders, Knees and Toes?” 🎶   Check out this quick game to test your coordination. Careful, it’s more difficult than it looks!

Many of our readers are familiar with particular muscles and tendons, becoming mini-experts themselves after sports injuries, orthopedic conditions, or surgeries after accidents. However, the Doctors of Physical Therapy, or DPT for short, are knowledgeable of an encyclopedia’s worth of information on overall human anatomy. Knowledge is power as the saying goes. 📚 So, we hope this series is a refresher for some, an introduction for others, and a helpful resource to all to continue learning. This series aim to help you understand why physical therapists give you those exercises that may seem so challenging at first.  One goal is for rhat targeted exercise program to lead to a lifestyle of taking care of your body and preventing injury as much as possible.

Last month, April, we featured the Knee. We discussed Knee Anatomy  ,   research in the field about treatments for ACL Rehabilitation and Physical Therapy for Knee Osteoarthritis .

Now it’s time to breakdown the parts of the shoulder!!

Your shoulders are extremely important to arm and neck movement, not something to shrug off!  May will be Shoulder Month so brush off your collar of what you remember about the muscle groups and follow along with us as we review and take a closer look at shoulder anatomy.



Where would we be without shoulders to lean on? Not very comfortable, that’s for sure. That’s why these athletes know they have to warm up their shoulders.  As you scroll through some gifs below, sit straight up and try doing 10 shoulder rolls forward and back.  Then, check yourself to see if you feel a little looser and less hunched over your phone or computer screen








Most people do not realize that the shoulder joint is really several joints that combine with muscles and tendons to allow the shoulder to function. Being held together with muscles and tendons allows multifaceted movement and mobility of the shoulder, but also can create an unstable environment if those muscles and structures are not supported and strong.



There are primarily 3 bones that make up the shoulder joint. They consist of the humerus, the upper arm bone, the scapula, the shoulder blade and the clavicle, also known as your collarbone.

The humerus is positioned into the rounded socket of your scapula. This socket is called the glenoid. A combination of different muscles and tendons holds the humerus in the glenoid. The muscles and tendons that hold the joint together are commonly known as the rotator cuff. These rotator cuff tissues begin at the head of the upper arm bone and attach to the shoulder blade (see fig. 1 and fig.2 for visual diagrams of structures).



Now let’s move on to MUSCLES! The most commonly known shoulder muscles consist of:

Deltoid -These are located on the cap of the shoulder with a triangle shape. The deltoid can be divided into 3 segments: Anterior, Middle and Posterior Deltoid.

Trapezius – This is located along the upper back and neck. Can be divided into 3 segments: Upper, Middle and Lower.

Supraspinatus – located underneath the upper trapezius muscle fibers.

Infraspinatus – located underneath a portion of the trapezius and a portion of the deltoid.

Subscapularis – located on the front (anterior) surface of the shoulder blade (scapula).

Teres Minor – small muscle located underneath the infraspinatus muscle.
*(see fig.3 for visual diagram)

Tendons in this area are tender!


The basic shoulder/rotator cuff tendons consist of:

The Supraspinatus Tendon –  This is located at the top/front (anterior) of the upper arm bone (humerus),

The Infraspinatus Tendon – This tendon is located on the back (posterior) side of the upper arm bone (humerus), seated above the teres minor tendon.

The Teres Minor Tendon – This tendon is located on the back (posterior) side of the upper arm bone (humerus), seated below the Infraspinatus tendon.

Supscapularis Tendon – This tendon is located at the front (anterior) side of the upper arm bone (humerus).

Biel, Andrew. Trail Guide To The Body: How To Locate Muscles, Bones And More. Fifth Edition. Boulder, CO : Books Of Discovery, 2014. Print.–conditions/shoulder-pain-and-common-shoulder-problems/
Fig 1 –

Fig 2 –

Fig 3 –